With the advent of heavy special purpose vessels, particularly offshore drilling vessels or other floating structures, it has become common practice to use anchoring systems comprising a plurality of relatively long anchor lines each including a heavy anchor chain connected to a wire rope. Typical systems employ from one to several thousand feet of anchor chain connected to the anchor and a length of wire rope connected to the end of the chain opposite the anchor. In order to handle such anchor lines, prior-art workers have developed combination wheels or sheaves having an inner groove dimensioned to accommodate the wire rope, and an outer groove, which may be pocketed, dimensioned to accommodate the chain. In some cases, it has been proposed to employ simple link connectors between the anchor chain and the wire rope, but the bending forces in the wire rope at the connection have proved too great for such an arrangement to be completely satisfactory. Accordingly, special connectors have been proposed, but these have suffered from limitations, such as a limit of about 90.degree. change in direction while traversing a wheel or sheave, or a requirement that the connection be oriented in a particular manner before it arrives on the wheel or sheave. The general state of the art is illustrated by the following U.S. Pats:
No. 3,583,354 Flickinger PA1 No. 3,792,622 Lyall PA1 No. 3,842,776 Wudtke
The concept of using two lines of different size connected by a special connection and handled by a combination wheel having concentric grooves to handle the two different size lines is adapted from earlier practice as shown, e.g., in U.S. Pat. No. 1,532,775 to Page. Though anchoring systems of the general type referred to have shown marked advantages over systems employing only an anchor chain or only a wire rope, there has been a continuing demand for improvement of such systems.